the difference between x402 and AP2

In plainer words

In short: both x402 and AP2 aim to let AI agents pay safely, but they cover different parts. x402 (driven by Coinbase) is about the payment action itself: an agent calls an endpoint, the endpoint says "this costs money," and the agent signs and pays from its wallet on the spot — no account, no key; the payment is the pass. It solves "how to turn one call into one charge." AP2 (driven by Google) is about the source of authorization: the user signs a mandate first (e.g. "may spend up to $50 on a flight"), and the agent carries that signature when it pays, so the merchant can confirm it's the user's real intent, not the agent freelancing. It solves "how to prove the payment was authorized." So they aren't either/or — more like different links in one chain: one governs "how to pay," the other "on what authority." The field is young; no clear winner. OceanAlt's compliance layer is deliberately protocol-neutral: whether you use x402, AP2 or something else, the pre-settlement compliance check plugs in.